https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104221
Nathaniel Shead <nathanieloshead at gmail dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |nathanieloshead at gmail dot com --- Comment #1 from Nathaniel Shead <nathanieloshead at gmail dot com> --- I think this is IFNDR; you cannot have more than one partition with the same name. See https://eel.is/c++draft/module.unit#3: > A module partition is a module unit whose module-declaration contains > a module-partition. A named module shall not contain multiple module > partitions with the same module-partition. All module partitions of a > module that are module interface units shall be directly or indirectly > exported by the primary module interface unit ([module.import]). > No diagnostic is required for a violation of these rules. And in particular, unlike a module implementation unit, a module partition does not implicitly import anything; see https://eel.is/c++draft/module.unit#8 which says: > A module-declaration that contains neither an export-keyword nor a > module-partition implicitly imports the primary module interface unit > of the module as if by a module-import-declaration. So this is working as specified. I don't think there'd be any good way of improving the diagnostics for this either.